On the CBS sitcom, future Ted (Bob Saget) revealed that his past self (Josh Radnor) will soon break up with his latest love interest (Jennifer Morrison).
Thomas told the Los Angeles Times: "We went out on a limb and told the audience through our narrator that this relationship will end badly. You could argue that knowing that kills the suspense. But it also whets one's appetite to see a truly grand train wreck of an ending."
He continued: "Zoey and Ted are a highly flammable couple. If you're a fan of horrible breakups, and really who isn't, [then] stay tuned!"
Thomas hinted that the issue of the new GNB tower that brought Ted and Zoey together could ultimately tear them apart.
"They're poised on opposite sides of a huge issue," he explained. "Their enmity on the issue... will definitely continue to complicate their relationship as season six progresses."
How I Met Your Mother, which was recently renewed for two more seasons, currently airs on Mondays at 8/7c on CBS.
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