Planescape campaign begining

[gammadelta1]

My friends and I have decided to put together a Pleanescape campaign and given the nature of the setting I've given a loose collar when it comes to creating characters. (I've been voted the GM) We haven't rolled them yet, but they have decided on the race and role. I have a human priest, A Ranger (elf I think), and a vampire. They were excited with the idea of primes being tossed into Sigil, and further as the campaign progresses. Now, I'm putting together a good arc. But I'm struggling with two parts. One is how to get this vampire to join the crowd with the other two as that would be the most difficult since on prime worlds vampires are natural enemies. The other is getting the ball rolling (they won't be level 1's). As any prime tossed into this idea of a multiverse it would be entirely overwhelming.

The first problem, I'm looking for any help what so ever.
The second, any experienced GM's who have run a campaign like this before.

As a side note, one of the long term goals is to obtain a journal from a well known planeswalker. It its text is lists of portals, their keys, and destinations. Survival notes for the outer planes. But this is mixed in with his personal notes and entries. Thinking like the journals from MYST or RIVEN. Any bookmaking ideas would be appreciated too.

Trust me, thank you for your help.

[Thrawn4]

My friends and I have decided to put together a Pleanescape campaign and given the nature of the setting I've given a loose collar when it comes to creating characters. (I've been voted the GM) We haven't rolled them yet, but they have decided on the race and role. I have a human priest, A Ranger (elf I think), and a vampire. They were excited with the idea of primes being tossed into Sigil, and further as the campaign progresses. Now, I'm putting together a good arc. But I'm struggling with two parts. One is how to get this vampire to join the crowd with the other two as that would be the most difficult since on prime worlds vampires are natural enemies. The other is getting the ball rolling (they won't be level 1's). As any prime tossed into this idea of a multiverse it would be entirely overwhelming.

The first problem, I'm looking for any help what so ever.
The second, any experienced GM's who have run a campaign like this before.

As a side note, one of the long term goals is to obtain a journal from a well known planeswalker. It its text is lists of portals, their keys, and destinations. Survival notes for the outer planes. But this is mixed in with his personal notes and entries. Thinking like the journals from MYST or RIVEN. Any bookmaking ideas would be appreciated too.

Trust me, thank you for your help.

The way I understand the setting, many inhabitants of Sigil are enemies to Primes, e. g. demons. So you should establish early on that the old standards do no longer apply.
The best solution to make characters work together is to establish common goals early on that are important to everyone. Maybe there is a reason why they were drawn into the multiverse, maybe they are cursed or they are likely to die if they do not cooperate. Maybe the first page of the planewalkers journal indicates that they should work together.

Some other questions:
How are you going to deal with the vampires weakness to sunlight?
Which system and which rulebooks are you using?
Are you familiar with planewalker.com?

[Shadowsend]

You may want to start the party off in Ysgard so that they can work through their differences and figure out themselves as a party before engaging in any real story. Unfortunately, that would deny the vampire and possibly any demons that relied on negative energy. Otherwise, you can definitely kick the tires quite well there.

[Kid Jake]

First thing that jumps out to me is that maybe the elf and human WERE enemies with the vampire on the Prime. It could be an immensely amusing scenario to basically start off with the vampire bwahahaing about how they've fallen into his clutches and then by a series of zany, sitcom like coincidences they're all thrown into Sigil together.

They're awestruck and terrified by what they see there and the old adage of 'the devil you know....' encourages them to team up to survive.