In a plot described as the soap's "hottest ever", the former lovers will be seen meeting for secret sex sessions all over Albert Square, including the car lot office - where Tanya's new husband Greg nearly catches them.
"Max and Tanya are one of the hottest couples in EastEnders' history," a source told the Daily Star Sunday. "The on-screen chemistry between Jo Joyner and Jake Wood has always been through the roof, but this affair is going to take it to a whole new level.
"Those scenes in the car lot are very racy. Max pulls his trousers down as Tanya rips off her clothes - they're rampant.
"It is going to be the sexiest affair Walford has seen. They don't care where they do it, as long as they get to spend some time together."
Tanya previously cheated on Greg on her wedding day.
> Max pursues Tanya at his engagement party
> Max and Tanya have a close call